I'm getting following exception when i try to create Java Business Hosts and import the jar files, i have implemented with PEX BO/BS

The selected file does not contain any classes which can be imported as a java business host.  Try selecting a different jar file

yes , its showing the required class files...is there any JDK version issues or any configuration required

I have all the required class files and dependencies , I'm facing some crazy issue , while setting up Java host, when I try to import Jar file , it tells class files doesn't exist , but if I unzip the jar files , I can all the class files